Neue Technologie beim Altglasrecycling: die Glasvermahlung

Die Anforderungen an die Altglasaufbereitung nehmen ständig zu. Vor diesem Hintergrund wurde in den USA eine neue Technik entwickelt, die diesen Anforderungen hinlänghch gerecht wird. Es handelt sich dabei um die Glasvermahlung, welche die konventionelle teure KSP und Allmetallabscheidetechnik ergänzt oder sogar ersetzt. Durch die Verbindung des differentiellen und autogenen Mahlens (differential und autogenetic grinding) wird nur das Glas zermahlen, während die Verunreinigungen ihre Größe beibehalten. Dadurch kann das gereinigte, feingemahlene Glaspulver abgesiebt werden, und die Verunreinigungen werden ausgeschleust. In den USA sind seit 1991 mehrere dieser Anlagen erfolgreich im Betrieb. Erste Pilotanlagen in Europa werden diesen zukunftsweisenden Trend bestätigen. Durch die gezielte Auswahl und Kombination konventioneller und neuer innovativer Techniken ist es möglich, den ständig steigenden Anforderungen an das aufbereitete Altglas bei gleichzeitig sinkenden Investitionskosten gerecht zu werden

THz streak camera performance for single-shot characterization of XUV pulses with complex temporal structures

The THz-field-driven streak camera has proven to be a powerful diagnostic-technique that enables the shot-to-shot characterization of the duration and the arrival time jitter of free electron laser (FEL) pulses. Here we investigate the performance of three computational approaches capable to determine the duration of FEL pulses with complex temporal structures from single-shot measurements of up to three simultaneously recorded spectra. We use numerically simulated FEL pulses in order to validate the accuracy of the pulse length retrieval in average as well as in a single-shot mode. We discuss requirements for the THz field strength in order to achieve reliable results and compare our numerical study with the analysis of experimental data that were obtained at the FEL in Hamburg - FLASH. © 2020 Optical Society of America under the terms of the OSA Open Access Publishing Agreemen

Lateglacial and Holocene climate and environmental change in the northeastern Mediterranean region: Diatom evidence from Lake Dojran (Republic of Macedonia/Greece)

The juncture between the west-east and north-south contrasting Holocene climatic domains across the Mediterranean is complex and poorly understood. Diatom analysis of Lake Dojran (Republic of Macedonia/Greece) provides a new insight into lake levels and trophic status during the Lateglacial and Holocene periods in the northeastern Mediterranean. Following a very shallow or even desiccated state at the core base at ca. 12,500 cal yr BP, indicated by sedimentological and hydro-acoustic data, diatoms indicate lake infilling, from a shallow state with abundant benthos to a plankton-dominated relatively high lake level and eutrophic state thereafter. Diatom-inferred shallowing between ca. 12,400 - 12,000 cal yr BP and a very low lake level and eutrophic, oligosaline state between ca. 12,000 - 11,500 cal yr BP provide strong evidence for Younger Dryas aridity. The earliest Holocene (ca. 11,500 - 10,700 cal yr BP) was characterised by a high lake level, followed by a lake-level reduction and increased trophic level between ca. 10,700-8,500 cal yr BP. The lake was relatively deep and exhibited peak Holocene trophic level between ca. 8,500-3,000 cal yr BP, becoming shallow thereafter. The diatom data provide more robust evidence and strengthen previous lake-level interpretation based on sedimentological and geochemical data during the earliest, mid and late Holocene, and also clarify previous uncertainty in interpretation of Lateglacial and early-Holocene lake-level change. Our results are also important in disentangling regional climate effects from local catchment dynamics during the Holocene, and to this end we exploit extant regional palynological evidence for vegetation change in the highlands and lowlands. The importance of seasonality in driving Holocene climate change is assessed by reference to the summer and winter latitudinal temperature gradient (LTG) model of Davis and Brewer (2009). We suggest that increased precipitation drove the high lake level during the earliest Holocene. The early- Holocene low lake level and relatively high trophic state may result climatically from high seasonality of precipitation and locally from limited, nutrient-rich catchment runoff. We argue that the mid- Holocene relatively deep and eutrophic state was driven mainly by local vegetation succession and associated changes in catchment processes, rather than showing a close relationship to climate change. The late-Holocene shallow state may have been influenced by a temperature-induced increase in evaporative concentration, but was coupled with clear evidence for intensified human impact. This study improves understanding of Lateglacial and Holocene climate change in the northeastern Mediterranean, suggests the important role of the LTG on moisture availability during the Holocene, and clarifies the influence of catchment processes on palaeohydrology

Ephrin-A5 Suppresses Neurotrophin Evoked Neuronal Motility, ERK Activation and Gene Expression

During brain development, growth cones respond to attractive and repulsive axon guidance cues. How growth cones integrate guidance instructions is poorly understood. Here, we demonstrate a link between BDNF (brain derived neurotrophic factor), promoting axonal branching and ephrin-A5, mediating axonal repulsion via Eph receptor tyrosine kinase activation. BDNF enhanced growth cone filopodial dynamics and neurite branching of primary neurons. We show that ephrin-A5 antagonized this BDNF-evoked neuronal motility. BDNF increased ERK phosphorylation (P-ERK) and nuclear ERK entry. Ephrin-A5 suppressed BDNF-induced ERK activity and might sequester P-ERK in the cytoplasm. Neurotrophins are well established stimulators of a neuronal immediate early gene (IEG) response. This is confirmed in this study by e.g. c-fos, Egr1 and Arc upregulation upon BDNF application. This BDNF-evoked IEG response required the transcription factor SRF (serum response factor). Notably, ephrin-A5 suppressed a BDNF-evoked neuronal IEG response, suggesting a role of Eph receptors in modulating gene expression. In opposite to IEGs, long-term ephrin-A5 application induced cytoskeletal gene expression of tropomyosin and actinin. To uncover specific Eph receptors mediating ephrin-As impact on neurotrophin signaling, EphA7 deficient mice were analyzed. In EphA7 deficient neurons alterations in growth cone morphology were observed. However, ephrin-A5 still counteracted neurotrophin signaling suggesting that EphA7 is not required for ephrin and BDNF crosstalk. In sum, our data suggest an interaction of ephrin-As and neurotrophin signaling pathways converging at ERK signaling and nuclear gene activity. As ephrins are involved in development and function of many organs, such modulation of receptor tyrosine kinase signaling and gene expression by Ephs might not be limited to the nervous system

Radikale Innovationen heißt radikal Umdenken

Mehr und mehr setzen massiv finanzierte Start-Ups etablierte Unternehmen unter Druck. Legten viele Unternehmen bisher den Fokus auf Kosteneinsparungen und inkrementelle Verbesserungen ihres Produktportfolios, so müssen sie heute verstärkt an radikalen Innovationen arbeiten, die das Potenzial bergen, auch die zukünftige Geschäftstätigkeit ihres Unternehmens zu sichern. Konventionelle Stage-Gate-Prozesse haben sich für diese Art von Innovationen aufgrund ihrer Behäbigkeit als nicht optimal herausgestellt. Radikale Innovationen brechen mit Althergebrachtem. Sie erfordern neue, flexible Denkweisen und Prozesse. Die neuen Player machen es vor: Geschwindigkeit und Leichtigkeit sind das Geheimnis ihres Erfolgs. Bereits 2003 legte EVERSHEIM mit dem W-Modell den Grundstein für das Innovationsmanagement von heute, das sich im Invention Center auf dem RWTH Aachen Campus manifestiert hat und als Systemlösung für ein modernes Management disruptiver Innovationen verstanden wird. Das Invention Center hat sich zu einem einmaligen und robusten Netzwerk aus Zukunftsmanagern entwickelt, welches mit modernen Ansätzen und Methoden aus dem Technologie- und Innovationsmanagement erfolgreich den Herausforderungen der heutigen Zeit begegnet

Optimizing Inter-Cluster Flights of Post-Disaster Communication Support UAVs

In the aftermath of large-scale disasters, critical communication infrastructure is often destroyed. Ad hoc networks can restore wireless communication with basic functionalities, especially for civilians in the affected areas. However, as humans form groups and tend to stay around important locations like shelters in such situations, the network is highly intermittent. Autonomous Unmanned Aerial Vehicles can act as controllable and highly mobile data carriers between separated network clusters to enable delay-tolerant inter-cluster communication. A possible heterogeneous set of usable aerial vehicles and the necessity to adapt the system to various environments requires the system to be highly flexible. Combined with severe constraints in energy usage or number of available vehicles, there is a need to increase the efficiency of inter-cluster flights. In this paper, we present approaches to optimize inter-cluster flights based on communication performance and energy efficiency. The resulting optimization model is a powerful tool for operators to adjust system settings to match required demands

Women's dietary diversity scores and childhood anthropometric measurements as indices of nutrition insecurity along the urban–rural continuum in Ouagadougou, Burkina Faso

Background: Malnutrition is still prevalent worldwide, and its severity, which differs between regions and countries, has led to international organisations proposing its inclusion in the global development framework that will succeed the Millennium Development Goals (post-2015 framework). In Sub-Saharan Africa, malnutrition is particularly severe, among women and children under 5 years. The prevalence of malnutrition has been reported worldwide, differing from region to region and country to country. Nevertheless, little is known about how malnutrition differs between multiple locations along an urban–rural continuum. Objective: A survey was carried out in and around Ouagadougou, Burkina Faso, between August and September 2014 to map household nutrition insecurity along the urban–rural continuum, using a transect approach to guide the data collection. Design: Transects of 70 km long and 2 km wide directed radially from the city centre outwards were laid, and data were collected from randomly selected households along these transects. Women's dietary diversity scores (WDDSs) were calculated from a sample of 179 women of reproductive age (15–49 years) from randomly selected households. Additionally, anthropometric data (height/length and weight) of 133 children under 5 years of age were collected along the same transects for the computation of anthropometric indices. Results: We found that relative proportions of the nutrition indices such as stunting, wasting and underweight varied across the urban–rural continuum. Rural households (15%) had the highest relative proportion of WDDS compared with urban households (11%) and periurban households (8%). There was a significant association between children under 5 years’ nutritional status (wasting, stunting and underweight) and spatial location (p=0.023). The level of agricultural activities is a possible indicator of wasting in children aged 6–59 months (p=0.032). Conclusion: Childhood undernutrition certainly has a spatial dimension that is highly influenced by the degree of urbanity, which should be taken into consideration in policy formulation and implementation

On the topographic targeting of basal vomeronasal axons through Slit-mediated chemorepulsion

The vomeronasal projection conveys information provided by pheromones and detected by neurones in the vomeronasal organ (VNO) to the accessory olfactory bulb (AOB) and thence to other regions of the brain such as the amygdala. The VNO-AOB projection is topographically organised such that axons from apical and basal parts of the VNO terminate in the anterior and posterior AOB respectively. We provide evidence that the Slit family of axon guidance molecules and their Robo receptors contribute to the topographic targeting of basal vomeronasal axons. Robo receptor expression is confined largely to basal VNO axons, while Slits are differentially expressed in the AOB with a higher concentration in the anterior part, which basal axons do not invade. Immunohistochemistry using a Robo-specific antibody reveals a zone-specific targeting of VNO axons in the AOB well before cell bodies of these neurones in the VNO acquire their final zonal position. In vitro assays show that Slit1-Slit3 chemorepel VNO axons, suggesting that basal axons are guided to the posterior AOB due to chemorepulsive activity of Slits in the anterior AOB. These data in combination with recently obtained other data suggest a model for the topographic targeting in the vomeronasal projection where ephrin-As and neuropilins guide apical VNO axons, while Robo/Slit interactions are important components in the targeting of basal VNO axons